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Registered
1990 500 SEL, 2003 Range Rover HSE
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2,073 Posts
Discussion Starter · #1 ·
Hello everybody.

It seems the AC has a gas leak somewhere and I'm totally frustrated about it.
Last time we had an AC repair it didn't only cost a lot of money but the interior
of the car suffered noticably. If you have an idea where to look first, I'll
appreciate your help.

Thanks in advance.
 

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Moderator
1991 500SEC 55K mi. 1987 560SEC Now 153K mi. 2020
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5,461 Posts
Hi Tahloube,

Sorry to hear the interior was damaged during the last A/C go round.

You may be in luck though.... If the previous shop introduced fluorescent dye into the refrigerant circuit, then it would be likely the residue would be apparent at the leak site when using black (ultraviolet) light and the special yellow tinted glasses.

The A/C shop I go to used this technique while diagnosing my system last year. There was a dramatic splash of bright green (under black light) right at the leak site. No mistaking where the R-12 went....

Perhaps the process will be similar with your car.

At any rate, the shop will have to hook up the gauges, and probably do an evacuate & recharge to properly start the diagnosis. If no dye is present - it could be added during the recharge........

Good Luck & Cheers, MBL
 

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Registered
1986 560SEL
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4 Posts
You can get a basic leak check kit for $20-$30 at most auto parts stores. It'll have an LED based UV penlight, goggles, and a can of dye w/a direct injector top so you don't need any extra tools. Only hitch is if you're still running R12 you'll need an R12 to R134 fitting adapter. The little pen lights aren't too bright so best to do the check at night or in a dark garage. If it's been worked on recently have a look around before putting in fresh dye to make sure you're seeing the current leak.
 

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Registered
1990 500 SEL, 2003 Range Rover HSE
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2,073 Posts
Discussion Starter · #4 ·
Thank you very much MBL87560SEC & Spinergy.
Your were really helpful.
 

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Banned
1992 W126 300 SE
Joined
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11,045 Posts
The guy that services my A/C says that the evaporator is a weak spot in the system.He also said to check the union nuts on the radiator-they suffer from electrolytic corrosion and split.
 

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Registered
1990 500 SEL, 2003 Range Rover HSE
Joined
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2,073 Posts
Discussion Starter · #6 ·
Thanks deathrattle.

I only wonder if you ever really need to use your ACs in England. I mean it was
48 C at the traffic lights the other day and I thought I should leave the car and
take a taxi.
 
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